Respiratory Substrates

Question 1

Carbohydrates

Answer 1

e.g starch are digested into glucose which can then enter glycolysis.

Question 2

Proteins

Answer 2

Hydrolysed into amino acids which are deaminated in the liver. The keto acid produced can be converted into acetate to be used in Krebs Cycle. Used as last resort as proteins essential in the body.

Question 3

Lipids

Answer 3

Digested into glycerol and fatty acids. Glycerol can be converted to TP and enter glycolysis. Each fatty acid can be converted into acetate and enter Krebs Cycle.

Question 4

Which has highest energy level?

Answer 4

Lipids - contain more C-H bonds which are broken to release lots of H atoms. This means more FAD and NAD are reduced during Krebs. This generates more ATP via the ETC and ATP synthase during oxidative phosphorylation.